Abstract: The root tip of six cultivars of Freesia hybrida was used as the plant material for karyotype analysis to reveal their karyotype characteristics. Then cluster analysis was performed to clarify the similarity among the six cultivars and to explore their relationship. The results showed that the six freesia cultivars were all tetraploid with 44 chromosomes. The karyotype formula of six cultivars of F. hybrida were as follows respectively:2n=4x=44=33m+11sm for‘Gold River’,2n=4x=44=1M+34m+9sm for‘White River’,2n=4x=44=35m+9sm for‘Castor’,2n=4x=44=32m+12sm for‘SN Hongtaige’,2n=4x=44=38m+6sm for‘Pink Passion’,and 2n=4x=44=37m+7sm for‘Red River’. The karyotype asymmetry coefficient ranged from 57.00% to 60.07%. The karyotype types were all 2B,and the degree of evolution was medium,which was in the transition stage from symmetry to asymmetric. The evolution trend of karyotype was:‘Pink Passion’→’Red River’→‘Gold River’→‘White River’→‘Castor’→‘SN Hongtaige’. The clustering results showed that when the genetic distance was 15,it could be divided into two categories:the first category included‘Gold River’,‘SN Hongtaige’and‘Castor’,the second category included‘Pink Passion’,‘Red River’and‘White River’. The difference of its karyotype parameters could be used as the basis for the classification of different cultivars of freesia plants,provided theoretical reference for its cytological inheritance and breeding practice in future.